Standard I.V. catheters are regularly used to infuse fluids into the bloodstream for medical purposes. In order to gain access to the bloodstream, a hollow tube or catheter must be placed within a blood vessel.
An I.V. catheter normally comprises a hollow bore needle with a sharpened distal end with the opposite, or proximal, end attached to a needle hub, with the proximal end of the needle being in communication with a hollow or "flashback" chamber of the needle hub, a separable flash plug sealingly closing the hollow chamber of the needle hub, and a separable catheter and catheter hub axially located about the needle.
A standard I.V. catheter is introduced into a blood vessel by means of a hollow bore needle whereby the catheter is placed axially on the needle and the sharp needle tip projects slightly beyond the distal end of the catheter. The sharp needle is used to pierce the skin and underlying tissue until the distal end of the catheter and needle enter the lumen, or fluid passageway, of the blood vessel. At this point, blood flows through the hollow bore of the needle and into the flashback chamber of the needle hub, indicating the catheter can be advanced into the blood vessel. At this point, the needle is held in a stationary position and the catheter is manually advanced into the blood vessel. When the catheter is properly inserted, manual pressure is placed on the catheter tube in the blood vessel to prevent blood from squirting out through the hollow bore of the catheter and the needle is withdrawn. A properly prepared and filled I.V. line is then attached to the catheter hub by an I.V. connector.
During the normal course of I.V. catheter placement, blood commonly fails to flow into the flashback chamber of the needle hub. This presents problems for both the healthcare worker and patient. In the current managed care environment, cost constraints place additional pressure on the healthcare worker to perform procedures safely, quickly and in a cost effective manner. The patient needs to be infused and the healthcare worker needs to complete the procedure and attend to the next task or patient. When blood fails to flow into the flashback chamber, the healthcare worker will most likely "fish" around with the I.V. catheter needle trying to properly locate the blood vessel. Many times this type of exploration is quite painful to the patient and may leave the patient's body tissue badly bruised and cut. Even after "fishing" to locate the blood vessel, blood still may not flow into the flash chamber of the needle hub.
The next step requires the healthcare worker to remove the flash plug from the needle hub and connect a sterile syringe to the proximal end of the needle hub. The syringe is used to create a suction, or sub-atmospheric pressure, within the hollow bore needle and flash chamber in hopes that blood will flow into the flashback chamber.
The healthcare worker must awkwardly attempt to keep the sharpened needle tip stationary in the patient while pushing the syringe toward the patient to maintain an airtight seal on the I.V. catheter needle hub, yet pull the syringe plunger rod away from the patient to create a suction within the inner chamber of the syringe and needle hub. Once blood appears in the flash chamber, the catheter usually can be advanced.
FIG. 1 illustrates a full and cross-sectional view of a prior art I.V. catheter introducer 140 that is used to place an I.V. catheter 113 into a blood vessel. The prior art I.V. catheter device has four primary components. These include: (1) a hollow bore needle 110 having a sharpened distal tip 111, with the proximal end of the needle 110 being fixedly attached to (2) a needle hub 120 with a hollow or "flashback" chamber 121 being in communication with the hollow bore of the needle 110, (3) a separable cap or "flash plug" 130 sealingly seated at the proximal end of the needle hub 120 creating the sealed, or vented, inner chamber 121, and (4) a separable catheter 113 attached to a catheter hub 112, catheter 113 axially surrounding the hypodermic needle 110.
FIG. 2 is a full and cross sectional view of a prior art I.V. catheter introducer and separable catheter shown in FIG. 1 having separable flash plug 130 being removed from needle hub 120. Flash plug 130 may also comprise an aperture or through hole which acts as a vent connecting the flashback chamber with the ambient atmosphere, said flash plug 130 having a filter membrane within which allows gaseous substances to pass through, but substantially prevents fluids from passing through said filter.
What is needed is an apparatus and method for introducing an I.V. catheter which does not at first require the use of another device, such as a syringe, to aspirate fluid or gaseous substances through the catheter needle and solves the aforementioned problems.